This paper shows that the intensity of violence in Rwanda’s recent past can be traced back to the initial establishment of its pre-colonial state. Villages that were brought under centralized rule one century earlier experienced a doubling of violence during the state-organized 1994 genocide. Instrumental variable estimates exploiting differences in the proximity to Nyanza — an early capital — suggest that these effects are causal. Before the genocide, when the state faced rebel attacks, with longer state presence, violence is lower. Using data from several sources, including a lab-in-the-field experiment across an abandoned historical boundary, I show that the effect of the historical state is primarily sustained by culturally transmitted norms of obedience. The persistent effect of the pre-colonial state interacts with government policy: where the state developed earlier, there is more violence when the Rwandan government mobilized for mass killing and less violence when the government pursued peace.